Hydrogen is an expensive commodity. The efficient use of hydrogen is very important to the economics of a hydroprocessing unit. In current designs of hydroprocessing units, there is a significant amount of hydrogen that is currently not being recovered, such as the hydrogen that ends up in the low pressure fractionation section of either a hydrotreating or hydrocracking unit. The present inventors have realized that if this hydrogen could be economically recovered and recycled to the makeup gas header, then it will reduce the amount of makeup hydrogen that would be required, thus reducing the operating cost associated with producing the hydrogen.